The present invention relates to a surface inspection method, surface inspection apparatus, and prism for inspecting the surface of an object of inspection.
When manufacturing small pieces such as short columnar or cylindrical parts, inspections are performed for performed for the presence of defects such as flaw, stain and uneven color on the inner and outer surface of the small pieces, and the defect rate of small pieces is lowered. In such inspection of the inner and outer surface, small pieces to be inspected are supported by proper means, rotated about the axial center, and the surface of the rotating small pieces is inspected visually or by camera, and the quality of surfaces of small pieces is evaluated on the basis of the visual or photographic results.
In such conventional inspection method, however, the small pieces to be inspected must be rotated, and a rotating mechanism is needed, which increases the inspection cost. Besides, since the small pieces must be rotated at least one revolution, the inspection time is longer, or some pieces may elude inspection if a slip occurs in rotation. Moreover, to inspect the surface of small pieces, a mechanism for conveying small pieces is needed, which also adds to the cost, and increases inspection time.